Process for producing monovinyl acetylene



Patented Nov. 19, 1940 PROCESS FOR PRODUOIN G MONOVINYL ACETYLENE Herbert Berg and Hans Helm, Burghausen, Upper Bavaria, Germany, Gesellschalt assignors and: Franz leiss, Munich, Bavaria,

to Alexander Wacker fiir Electrochemische Industrie,

'G. 111. b. H., Munich, Bavaria, Germany, a corporation of Germany No Drawing. Application July 1, 1931, Serial No.

152,374. In Germany July 17, 1 936 14 Claims.

This invention relates to the production of monovinyl acetylene and has for its object to provide a new and improved process for this purpose.

A related object of the inventionis to provide an improved process for producing monovinyl acetylene in the vapor phase by passing acetylene at elevated temperatures over solid coppercontaining ternary catalysts.

We have made the surprising discovery that process the expected explosive copper-acetylene composition is not produced, but that a practically complete transformation of the acetylene into monovinyl acetylene is effected without appreciable by-products, when the catalyst'is composed of three definite components'of the type hereinafter described. i v

The catalyst, according to our invention, comprises a cuprous salt whichis in itself useless, and which must be activated by suitable additions. Such activators, the efiect of which apparently rests on their complex formation with the cuprous salts, comprise nitrogen containing compounds of organic and inorganic nature, particularly basic-nitrogen compounds (that-- is, compounds having nitrogen in the cation), such. as urea, aniline chlorhydrate, ammonium salts, acid amide, amines, and similar substances, as well as multi-valent aliphatic hydroxyl compounds such as glycols, e. g. butylene glycol, glycerine, mannitol, 'sorbitol, dulcite, and the like; and, with these substances, salts of metals of the first, second, and third groups oif the periodic system are present with inclusion of rare earths, predominantly the water soluble ones, particularly the halogenides', e., g. chlorides. The production of the catalyst is appropriately effected in such a way that the initial products in dissolved or suspended condition are placed upon a suitable carrier and the latter is then dried. For instance, cuprous chloride, magnesium chloride and'glycerine are heated with some water and the suspension is placed upon appropriate carriers, e. g. potsherds, pumice stone and the like, upon which it is dried. After drying in an inert gas or in vacuum, the catalyst is ready for use. Of course it is also possible ,to produce the catalyst in such a manner that the desired compounds are formed on :the carrier bychemical combination. J

The acetylene reaction is preferably eflected at temperatures over 100 C. The temperature range, in which thecatalyst is active, changes according to the nature of the catalyst employed; in most cas s a range of 100-180 C. has been found sui able.

The process is not limited to any definite pressure,.but the course ofthe reaction may be influenced by changing the pressure. For example, by increasing the pressure the conversion is improved and the mono vinyl acetylene may be condensed and/or separated ofi from the waste gases by cooling with tap or main water.

It is advantageous to mix with the acetylene 'which enters the reaction chamber small quantitles of a volatile acid, such as acetic acid, propionic acid or butyric acid, or it may be thinned or diluted with inert gases such as nitrogen. Since the catalyst becomes very strongly heated during the reaction, it is generally advantageous to cool it, for example by external cooling of the reaction chamber, or by an excess of acetylene or by addition of an inert gas. Furthermore, through an excess of acetylene or admixture of an inert gas,.the monovinyl acetylene which is generated is very quickly removed from the reaction; chamber and thus the formation of by- .products is still furtherretarded. The gas which leaves the reaction chamber may .be used again in carrying out the reaction. Before being returned to the reaction chamber, the reaction products are appropriately removed, wholly or in part, as by cooling, absorption, adsorption, or dissolution, and fresh acetylene is advantageously added in accordance with the quantity used up.

The monovinyl acetylene obtained according I to the process herein described is suitably used for chemical conversions, as in the production of artificial masses and the like.

' Example 1 liters per hour is passed through the chamber at a temperature of 155-165 C. The tempera- .ture is advantageously held as constant as possible, which may be attained by artificial cooling or correspondi' g regulation of the acetylene supply. The react on products which are formed in a practically quantitative yield from) the converted acetylene are removedfrom the waste gas by cooling, compression or dissolution, said reaction products containing about 93-98% monovinyl acetylene. The acetylenewhich has notbeen converted may be again introduced" into the reaction chamber after addition of fresh acetylene.

Example 2 A mixture of 300 g. of cuprous chloride, 25 g. of magnesium chloride and '15 g. of urea is formed into a dough with 150 cc. of water and applied to pumice stone, after which it is dried in a nitrogen current. In other respects the process is carried out-as described in Example 1. The most favorable reaction temperature is between 135-145 C. The output corresponds to that mentioned above. If traces of organic acids, for instance acetic acid, propionic acid, or butyric acid are added to the acetylene, this facilitates the reaction.

Eicample 3 300 g. of cuprous chloride, 100 g. of aniline chlorhydrate and 25 g. of magnesium chloride are deposited upon pumice stone and dried, as indicated above. The most favorable reaction temperature when using this catalyst is between 155-165 C. The output of monovinyl acetylene corresponds to that of the above examples.

Example 4 A mixture of 300 g. of cuprous chloride, 95 g. of ammonium chloride and 30 g. of magnesium chloride is formed into a dough with 150 cc. of water and deposited upon activated carbon, after which it is dried in a nitrogen current. The most advantageous reaction temperature when using this catalyst is about 150-155C. The output of monovinyl acetylene corresponds to that of the above mentioned examples.

Example 5 which comprises passing acetylene at a temper-- ature of IOU-180 C. through a liquid-free, solid catalyst bed containing a cuprous chloride, magnesium chloride and an ammonium salt.

2. Process for producing monovinyl acetylene which comprises passing acetylene at a temperatureof IOU-180 C. through a liquid-free, solid catalyst bed containing a cuprous chloride, magnesiur'n chloride'and a salt of an organic base.

3. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of IOU-180 ,C. through a liquid-free, solid catalyst bed containing a cuprous chloride, magnesium chloride and an acid amide.

4. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of -180? C. through a liquid-free, solid catalyst bed containing a cuprous chloride, mag-' nesium chloride and ammonium chloride, said catalyst being applied on a carrier.

5. Process for'producing monovinyl acetylene which comprises passing acetylene at a temperaature of IOU- vC. through a liquid-free, solid catalyst bed containing a cuprous chloride, magnesium chloride and ammonium chloride, said catalyst being applied on a carrier and having its efliciency increased by admixing with the acetylene vapors a volatile carboxylic acid;

- liquid-free solid catalyst bed containing a cuprous fresh gas.

while replacing the 6. Process for producing monovinyl acetylene which comprises passing an excess of acetylene at a temperature of 100-180 C. through a liquidfree, solid catalystbed containing a cuprous chlo-l ride, magnesium chloride and ammonium chlo- 5 ride,said catalyst being applied on a carrier and having its efilciency increased by admixingwith the acetylene vapors a volatile carboxylic acid, removing the reaction product from the acetylene and returning the latter to the reaction zone while replacing the converted acetylene with fresh gas. I

7. Process for producing monovinyl acetylene which comprises passing acetylene through a salt, a water-soluble salt of another second group metal, and a basic-nitrogen compound.

8. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of 100-180 C. through a liquid-free solid catalyst bedcontaining a cuprous chloride, magnesium chlorideand a basic-nitrogen compound.

9. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of 100-180" C. through a liquid-free solid catalyst bed containing a cuprous salt, a watersoluble salt of another second group metal and a basic-nitrogen compound, said catalyst being applied on a carrier.

10. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of IOU-180 C. through a liquid-free solid catalyst bed containing a cuprous. salt, a watersoluble salt of another second groupmetal and a basic-nitrogen compound, the eiiiciency of said catalyst being increased by admixing with the acetylene vapors a volatile carboxylic acid.

11. Process for producing monovinyl acetylene which comprises passing an excess of acetylene at a temperature of 100-180" C. through a liquidfree solid catalyst bed containing a cuprous salt, a water-soluble salt of another second group metal, and a basic-nitrogen compound.

12. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of 100-180 C. through a liquid-free solid catalyst bed containing a cuprous chloride, magnesium chloride and a basic-nitrogen compound, the efiiciency of said catalys being increased by admixing'with the acetylene vapors a volatilecarboxylic acid'.

13. Process for producing monovinyl acetylene which comprises passing acetylene at a temperature of IUD-180 C. through-a liquid-free solid catalyst bed containing a cuprous chloride, mag- 55 nesium chloride and a basic-nitrogen compound, removing the reaction product from the acetylene and returning the latter to the reaction zone while replenishing the converted acetylene with 14. Process for producing 'monovinyLace'tylene- I which comprises passing acetylene at a temperature of 100-180 C. through a liquid-free solid catalyst bed containing a cuprous chloride, magnesium chloride and a basic-nitrogen compound, 65 said catalyst being applied on a carrier and having its efiiciency increased by admixing with the acetylene vapors a volatile carboxylic acid, removingthe reaction product from the acetylene and returning the latter to the reaction zone 70 converted acetylene with fresh gas. 7

HERBERT BERG. HANS HEIM.

- FRANZ LEISS. V I [is 

